Prostrate clarkia

Stems prostrate or decumbent, to 50 cm, sparsely puberulent. Leaves: sessile or subsessile; blade oblanceolate to elliptic, 1–2.5 cm, apex usually obtuse. Inflorescences prostrate, dense racemes, axis straight; buds erect. Flowers: floral tube 4–7 mm; sepals usually reflexed in pairs; corolla bowl-shaped, petals lavender-pink shading pale yellow basally, with reddish purple spot above base, 10–15 mm; stamens 8, subequal; ovary 8-grooved; stigma not exserted beyond anthers. Capsules 20–30 mm. Seeds brown or gray, 1–1.5 mm, scaly, crest 0.2 mm. 2n = 52.

Flowering May–Jul. Coastal bluffs in grasslands and closed-cone pine forests; 0–100 m; Calif.

Clarkia prostrata, like C. davyi, occurs only on coastal bluffs and adjacent low elevation pine forests along the Pacific coast, and in this case only in the California Central Coast Subregion in Monterey, Santa Barbara, Santa Cruz, and San Luis Obispo counties.

Clarkia prostrata is a hexaploid that combines the tetraploid genome of C. davyi and the diploid genome of C. speciosa. Clarkia prostrata is morphologically and ecologically very similar to C. davyi but can usually be distinguished by its larger flowers with a spot on each petal. It differs from C. speciosa by having smaller flowers with the stigma not exserted beyond the anthers.